Vibrator unit



M. E. NULSEN VIBRATOR UNIT Dec. 3, 1940.

Filed June 29, 1955 INVENTOR fizz/1 1k 17 lb a l'fl' ATTORNEY Patented Dec. 3, 1940 UNITED STATES VIBRATOR UNIT Marvin E. Nulsen, Indianapolis, Ind., assignor, by mesne assignments, to P. R. Mallory & Co. Inc., Indianapolis, Ind., a corporation of Delaware Application June 29,

8 Claims..

This invention relates to mechanical interrupter units for electrical systems and, more particularly, to magnetic interrupters of the type having vibratory reeds adapted to make and break electrical circuits.

The invention is applicable, for example, to contact interrupters of the type comprising a vibratory member or reed carrying contacts which are rapidly opened and closed during the vibrations of the reed to interrupt the current in the power supply circuit for radio receivers and the like.

An object of the present invention is to improve the operating characteristics of an interrupter of the above type.

Another object is to provide uniform and satisfactory operation over extended periods of time and after the device has been subjected to considerable wear and usage.

A further object is to insure perfect starting of the apparatus at all times.

Other objects of the invention will be apparent from the following description and accompanying drawing taken in connection with the appended claims.

According to one form of the present invention the above objects may be achieved by con-- trolling the flexibility of the reed member in interrupter units of the above type by punching, cutting or forming suitable cut-out portions in parts of said reed members and by providing suitable ribs in other parts thereof. This may be done. for example, by providing suitably located holes in the reed member or by providing suitable cut-away portions along the sides of the reed in order to increase their flexibility in places and by drawing or pressing suitable rib portionsor securing suitable rib members in other parts of the reed.

The invention accordingly comprises the features of construction, combination of elements, arrangement of parts, and methods of manufacture referred to above or which will be further brought out and exemplified in the disclosure hereinafter set forth, including the illustrations in the drawing, the scope of the invention being indicated in the appended claims.

For a fuller understanding of the nature and objects of the invention as well as for specific fulfillment thereof, reference should be had to the following detailed description taken in connection with the accompanying drawing, in which;

Figure 1 is a sectional elevation of the magnetic interrupter mechanism with parts broken away;

Ilii

1935, Serial No. 29,025

Figure 2 is a perspective view of a reed embodying one form of the invention:

Figure 3 shows a reed made according to a modified form of the invention;

Figure 4 shows a reed made according to a further modified form of the invention; and

Figure 5 shows a reed made according to another form of the invention.

While a preferred embodiment of the invention is described herein, it is contemplated that considerable variation may be made in the method of procedure and the construction of parts without departing from the spirit of the invention.

Referring to the drawing, Figure 1 shows the reed and contact members, with part of the supporting structure of an interrupter mechanism.

The mechanical interrupter unit comprises a U-shaped base i0 oi magnetic permeable material having electrlcal conductivity. The base ill is provided with a transversely extending midportion (not shown) from which project the two substantially parallel arms [2, l2. A magnetic coil i3 is provided with end plate ll 0! any suitable insulating material and a core of magnetic permeable material provided with a pole piece I! situated between said arms i2, i2.

Between the ends of arms I2, I! of base in is fixedly mounted one end of a vibratory reed 2| having the free end thereof extending toward the pole piece l8 and provided with a reed pole piece 22 disposed in offset relationship to the pole piece I8. A portion of the end of an arm I! of the base I0 is bent substantially at right angles to make contact with the fixed end of the vibratory reed It so that a complete magnetic circuit will be formed about said coil through the coil core. base l0, portion 20, reed 2|, reed pole piece 22, whereby the pole piece i8 serves as one pole of the magnetic coil i3 and the vibratory reed 2i provided with the reed pole piece 22 serves as the other pole of the magnetic coil.

The vibratory. reed 2| is provided with a pair of double-faced contacts 23 and 24 with the faces of each disposed on opposite sides of the vibratory reed 2i, as shown in Figures 1 and 2.

Between one side oi the clamped end of the vibratory reed 2i and the end 0! one 0! the base arms l2, I2 is mounted a pair 01 spaced spring arms 25 and 2B insulated from both the arm I! and the vibratory reed 2| by sheets of insulating material 21. In like manner a similar pair of spring arms 28 and 28 are mounted between the other base arm I2 and the vibratory reed I I. The assembly is secured together by bolts ill projecting through holes in the end of one or the arms I2,

I! and threaded into tapped holes in the other arm II. Contact between the bolts and the spring and reed assembly is prevented by insulating collars ii.

The spring arms 2! and 2! are provided with circuit contacts I! and 31 respectively and spring arms 2| and 2! are provided with circuit contacts 34 and SI respectively. The circuit contact points 32 and N are adapted to cooperate with the double faced contact 21 and the circuit contacts I3 and IS with double faced contact 2. Adjustment of the gaps between these cooperating contacts is obtained through the use of adJustable supports 36 for each of the free ends of the spring arms 2|, 2, 2| and 20.

The reed member I! is preferably formed 0! a magnetically permeable metal and is 0! such dimensions and of such metallurgical treatment and composition as to provide a flexible member with its free end, carrying pole piece 22, adapted to oscillate responsive to interrupted magnetic impulses generated by coil it. It has been found, however, that if a reed member is constructed in the usual manner from a piece of metal of uniform thickness throughout that the stiiiness may be undesirably high in places thus rendering starting dimcuit, especially after the contacts have become considerably worn, and at the same time the reed will not be stitl' enough in other places, resulting in premature breakage or undesirable secondary vibrations.

It is proposed, therefore, according to the pressent invention, to increase the flexibility of the reed in places by providing cutaway portions of desired shape, location and dimensions and to increase the stiiiness of the reed in other places by providing ribs at these other places.

In the form of the invention illustrated in Figures 1 and 2 the cut-away portion comprises punched hole ll located between the contacts 23 and 2| and the clamping insulating sheets 21, preferably very close to the clamping sheets. The size of the hole is determined by the degree of flexibility required.

The stiffening members consist of ribs 4! drawn or pressed in the reed itself. The reed is preferably made from a steel of suflicient ductility to enable these ribs to be formed. If clock spring type of steel is used the drawing of the ribs can preferably be done before tempering. As shown in Figures 1 and 2 the ribs ll serve to prevent undesired secondary vibrations or oscillations in the end of the reed which would interfere with the normal motion of the reed. Likewise they serve to prevent breakage at this point after repeated operation over an extended period of time.

According to the modified form of the invention shown in Figure 3 the flexibility is achieved by punching a plurality of smaller holes 50 of desired size, shape and location in reed II. In this figure only one centrally located contact 23a is shown and the stiffening ribs ii are placed alongside the contact parallel to the edges of the reed in order to prevent breakage at the contact, where the greatest bending iorces are encountered.

Figure 4 shows another modified form of the invention in which greater flexibility is obtained by providing cut-away portions 60 along the sides of the reed. A stiffening rib Si is here shown between the two contacts 23 and 24 to prevent breakage in the region of the contacts.

In the modification shown in Figure 5 a transverse groove or hollowed portion III across the ill in Figures 1 and 2. provide body of the reed is provided so that a thinner area will be provided extending entirely across the reed body. If desired, the groove my extend only part of the distance across the reed. In this modification a plate member II is riveted or welded across the reed underneath the single contact 230 to serve as a lateral and longitudinal stiffener.

Not only does the present invention make it possible to adjust any reed to obtain a desired flexibility at all points along its length but it provides a method which is economical and simpie from a manufacturing standpoint. Likewise the above method of adjustment of the flexibility may be used to correct and improve the operation of interrupters which have been in use for a considerable period and have become worn and out of adjustment.

In operation 01' the device the magnetic coil is is first energized to draw pole piece 22 toward pole piece II. This causes contacts 23 and 24 on reed 2i and co-operating contacts 34 and 35 on spring arms 28 and 29 to close. with the circuit arrangements most commonly used for this type of device contacts 2!, $5, in closing, shortcircuit the magnet coil is thereby de-energizing it and allowing the reed member 2| to spring back and momentarily close contacts 23, 32 and 24, 33. The short-circuiting contacts being now open the process is repeated to continuously produce a vibratory motion in the reed and inter mittently close the contacts on the reed and spring arms. The cut away portions, such as the required flexibility to insure starting and to insure perfect contacting during operation. The rib portions, such as ribs 4| in Figures 1 and 2 prevent undue flexing at points of severe strain or undesired activity.

While the structure and arrangements described are cited to exemplify the type of device to which the present invention is applicable it is obvious that the invention is also applicable to a considerable variety of forms of mechanism and circuit.

While the present invention as to its objects and advantages, has been described herein as carried out in specific embodiments thereof, it is not desired to be limited thereby but it is intended to cover the invention broadly within the spirit and scope of the appended claims.

What is claimed is:

1. In a magnetic interrupter, a base member. an electromagnet mountz d thereon. a vibratory reed member having one end clamped to said base and the other end free to vibrate within the sphere of magnetic influence of said electromagnet, a first contact mounted on said reed member, a second contact supported from said base and co-operating with said first contact to open and close a circuit, said reed having portions formed at different parts of its length between lts clamped and free end to locally correct the flexibility characteristics thereof, one of said portions being formed with a smaller cross section than portions on either side thereoi whereby the flexibility is increased and another of said portions being provided with a stiffener of material extending above the surface of the reed.

2. In a magnetic interrupter, a base member, 7

supported from said base and co-operating with said first contact to open and close a circuit. said reed member having a hole punched through a portion thereof, said portion being located between said clamped end and said contact and said reed having a stiiifening rib located between said hole and said free end.

3. A vibratory member for a magnetic interrupter comprising a metal reed oi. substantially uniform width and thickness and having one end adapted to be clamped to a base and the other end adapted to serve as a vibratory portion, a contact mounted on said reed intermediate of said ends, a first portion intermediate of one of said ends and said contact having a hole punched therethrough to increase the flexibility of said portion and a second portion intermediate of the other of said ends and said hole having a stiilening rib formed therein to decrease the flexibility of said second portion.

4. A vibratory member for a magnetic interrupter comprising a metal reed of substantially uniform width and thickness and having one end adapted to be clamped to a base and the other end adapted to serve as a vibratory portion, a contact mounted on said reed intermediate of said ends and a portion having inwardly extending cuts along the edges of said reed intermediate of one oi said ends and said contact whereby the cross-sectional area of said portion is less than that of the remainder 01' said reed.

5. A vibratory member for a magnetic interrupter comprising a metal reed of substantially uniform width and thickness and having one end adapted to be clamped to a base and the other end adapted to serve as a vibratory portion, a portion of said reed between its clamped and vibratory ends being formed with a smaller cross section than portions on either side thereof, a contact mounted on said reed intermediate of said ends and a stiflening rib across said reed in the immediate vicinity of said contact.

8. In a magnetic interrupter, a base member, an electromagnet mounted thereon, a vibratory reed member having one end clamped to said base and the other end tree to vibrate within the sphere oimagnetic influence of said electromagnet, a firstcontact mounted on said reed, a second contact supported from said base and cooperating with said first contact to open and close the circuit, said reed member having a re-enIorcing rib located between said clamped end and said free end, the cross sectional area 01' said reed being substantially the same in a section through said re-eni'orcing rib and a section through said reed beyond the end or said re-eni'orcing rib.

7. In a magnetic interrupter, a base member, an electromagnet mounted thereon, a vibratory reed member having one end clamped to said base and the other end free to vibrate within the sphere oi magnetic influence of said electromagnet, a first contact mounted on said reed member. a second contact supported from said base and cooperating with said first contact to open and close a circuit, said reed member having a reeni'orcing rib located between said clamped end and said free end, said rib being an integral part or said reed member and comprising a projecting bump on one race of said reed and a correspond-,

ing depression on the other face thereof.

8. In a vibratory interrupter device, the combination of a base, an electromagnet mounted thereon and a flexible vibratory reed mounted thereon, one end oi said reed being clamped to said base and the other end being free to vibrate under influence of said electromagnet, a first contact supported on said reed, a second contact supported from said base and co-operating with said first contact to open and close a circuit during vibration or said reed, a rigid plate secured to the face of said reed intermediate the clamped and free end thereof and supporting said first contact and said reed having material removed from substantially its entire width in the region between its clamped end and said rigid plate to reduce its cross-sectional area and locally in- MARVIN E. NULSEN- crease its flexibility. 

